浙大PAT 2-07. 素因子分解 （解题思路）

2-07. 素因子分解

1024

1024=2^10

1323

1323=3^3*7^2

97532468

97532468=2^2*11*17*101*1291

1

1=1

3

3=3

#include <iostream>
#include <cmath>
using namespace std;

int main()
{
long int N;
cin>>N;
int i;
bool firstFlag = true;
long int tn = N;
cout<<N<<"=";
if(N == 1)
{
cout<<"1"<<endl;
return 0;
}
for(i = 2; i <= sqrt(tn)+1; ++i)
{
int count = 0;
while(N%i == 0)
{
N /= i;
count ++;
}
if(count)
{
if(firstFlag)
firstFlag = false;
else
cout<<"*";
if(count == 1)
cout<<i;
else
cout<<i<<"^"<<count;
}
count = 0;
}
if(N > 1)
cout<<N;
cout<<endl;
return 0;
}